Of all the product lines Apple has, the iPad is their product line with the most flexible pricing. Everything from the $250 base model up to the iPad Pro at $1000 ($1,350 with the keyboard). If you don't need the iPad Pro, there are three other models below that.
Even their highest priced iPads aren't very expensive. If you are a business buying a computer, it's less than one week's wages for the most expensive iPad.
> It's like they designed a product for a real niche
You have this almost exactly the opposite. The iPad is the mainstream product and the PC is the niche product. The overwhelming majority of people can do everything they need on the iPad. It's the niche users (Developers, Video Editors, etc) who require the additional flexibility a PC offers.
> you can get the new Macbook Air they just announced for basically the same exact cost as an iPad Pro + keyboard, and that comes with a full-featured OS.
Fundamentally, you get a MacBook (or Windows/ Linux) if you need the flexibility of having a desktop PC. A lot of people prefer the simplicity iPadOS offers.
Also, it's not just the most expensive iPad Pro versus the least expensive Mac. If you don't need the pencil or the nicer keyboard, you could get the iPad Air or the base iPad for significantly less.
> but you're getting a better OS on a computer with better specs.
You are confusing more flexible for better. The two operating systems target different purposes. For a lot of people the iPad OS is the better experience. Also, I haven't seen the benchmarks yet, but I suspect that like with the prior generation, this iPad Pro is significantly faster than the base MacBook Air.
It really comes down to form factor and OS.
The iPad Pro is expensive, but “Pro” implies you want a device that can do things which are useful to professionals.
As a developer, I am better served by an actual MBP for work and a cheap iPad for less-productive tasks, but not everyone is a developer.
The original argument for tablet computers in the first place was that sometimes you don't need a full-fledged computer, so you pocket $400-500 and get something cheap instead that's a limited but still quality device. And I think that would still be true with the iPad Pro. You want something that's closer to a full computer, with a real keyboard, but you still want to pocket some money.
Except... the pricing is awful.
It's like they designed a product for a real niche, and then stopped thinking about that niche as soon as they got out of the design phase and started working on implementation.
As a point of comparison, even if you hate Windows with a passion, you can get the new Macbook Air they just announced for basically the same exact cost as an iPad Pro + keyboard, and that comes with a full-featured OS. Is a Macbook Air as portable? Maybe not, but it's still pretty darn portable.
You're giving up the pencil, but you're getting a better OS on a computer with better specs. But I guess if you're a digital artist, and you prefer the iPad pencil over the Surface pen or Wacom tablets, and having a full OS doesn't matter for you -- this might be exciting. That seems like it would be a narrow demographic, but what do I know? I'm sure it'll sell well.